GE Sensing RPT 301, User Manual

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RPT 301 User Manual 23
K177 Issue No. 3
4 Calibration
The instrument is supplied with a calibration certificate. For the
instrument to stay accurate it is recommended that it is checked every
12 months.
The use of a Class A compensated deadweight pressure standard is
recommended.
The following procedures should be carried out in a controlled
environment by qualified personnel.
If the accuracy of the instrument is not within the specification, carry out
a calibration adjustment procedure.
A qualified person must have attended a product training
course given by the manufacturer or appointed agent and
successfully completed the training course on this equipment.
The manufacturer offers a comprehensive and, if required,
NAMAS accredited calibration service.
Calibration Check
A calibration check should be carried out at chosen intervals. The
readings of the instrument should be compared with a pressure standard
and, after any adjustments for accuracy (traced to National Standards),
the differences recorded. The adjusted differences can then be
compared with the required accuracy for the instrument. If necessary
a calibration adjustment can be carried out.
The recommended procedure is to check at increasing and then
decreasing intervals of 0, 20, 40, 60, 80 and 100% of full-scale.
C - User Calibration (Linearity/Drift Compensation)
This command performs a `best straight line fit' to the remaining errors
of the transducer or does a single pressure point correction. Entering
one pressure point causes the offset between the transducer and the
pressure standard to be added/subtracted across the whole pressure
range. Entering two pressure points (near zero and near full-scale)
cancels zero and full-scale drift. Entering more pressure points reduces
the remaining non-linearity and makes the zero and full-scale correction
more accurate.